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G Blanco

Publications and source records attributed to G Blanco.

At least 91 records · Page 5Linked to original sources
PubMed1996

Protein and microsatellite single locus variability in Salmo salar L. (Atlantic salmon).

We describe genetic variation at three microsatellite single loci and six allozyme loci of seven natural Atlantic salmon populations from Ireland and Spain. A comparison of genetic variability detected at both types of loci is performed. Also, the relative value of microsatellite single locus variability with regard to the identification of individual salmon populations is assessed. Microsatellite loci are shown to display higher levels of variation than allozyme loci. Mean number of alleles (6 +/- 1.53) and heterozygosity (0.46 +/- 0.04) at microsatellite loci are greater than those found for allozymes (1.85 +/- 0.05 and 0.21 +/- 0.03, respectively), and some microsatellite alleles appear to be specific for a location or geographical area. Allozyme and microsatellite variation show the same pattern of differentiation between populations with Irish and Spanish populations grouped into different clusters. However, greater values of genetic distance were found among microsatellite (D = 0.0747 +/- 0.011) rather than among allozyme loci (D = 0.0449 +/- 0.008). These results provide evidence that microsatellite-based analysis of genetic variation will be useful in the identification of individual populations of Atlantic salmon.

Alleles↗
PubMed1995

Comparison of the enzymatic properties of the Na,K-ATPase alpha 3 beta 1 and alpha 3 beta 2 isozymes.

The coexpression of multiple isoforms of the alpha and beta subunits of the Na,K-ATPase in mammalian tissues gives rise to the complex molecular heterogeneity that characterizes the Na pump. The expression of the different Na,K-ATPase isoforms in insect cells using recombinant baculoviruses represents a useful system for the analysis of Na,K-ATPase isoform function. In the present study, we use this system to direct the expression of the rat Na,K-ATPase alpha 3 beta 1 and alpha 3 beta 2 in sf-9 cells, a cell line derived from the ovary of the fall armyworm, Spodoptera frugiperda. The association of alpha 3 with either beta 1 or beta 2 results in catalytically competent Na,K-ATPase isozymes. Analysis of the kinetic characteristics of these enzymes demonstrates that the accompanying beta subunit isoform does not drastically affect the properties of the alpha 3 polypeptide. This is evidenced by the similar turnover numbers, apparent affinities for K+ and ATP, and the comparable high sensitivity to ouabain exhibited by both isozymes. The kinetic dependence on Na+, however, is different for both isozymes, with alpha 3 beta 2 displaying a 1.6-fold higher apparent affinity for the cation than alpha 3 beta 1. Comparison with other Na,K-ATPase isozymes shows that the apparent Na+ affinity of alpha 3 beta 2 is similar to that of the alpha 1 beta 1 Na pump widely expressed in every tissue; nevertheless, its reactivity toward K+, ATP, and ouabain are characteristic of the alpha 3 isoform. The most pronounced kinetic differences in Na,K-ATPase function are a result of variations in alpha isoform composition.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1995

A cytoplasmic region of the Na,K-ATPase alpha-subunit is necessary for specific alpha/alpha association.

While most structural studies of the Na,K-ATPase support a subunit stoichiometry of one alpha-subunit to one beta-subunit, the exact quaternary structure of the Na,K-ATPase and its relevance to enzyme function is the subject of much debate. Formation of a higher order enzyme complex is supported by our previous study demonstrating specific alpha/alpha interactions among the rat Na,K-ATPase isoforms (alpha 1, alpha 2, alpha 3), expressed in virally infected Sf-9 insect cells and among native alpha isoforms in rat brain (1). This detergent-resistant association was not observed in insect cells coexpressing the homologous gastric H,K-ATPase alpha-subunit, nor was it dependent on the coexpression of the beta-subunit. To delineate domains necessary for alpha/alpha assembly, a series of H,K-ATPase-Na, K-ATPase chimerase were constructed by combining the N-terminal, cytoplasmic midregion and C-terminal segments derived from the Na,K-ATPase (N) and the H,K-ATPase (H) alpha-polypeptides (HNN, HNH, NHH, NHN, and HHN). The alpha-subunit chimeras were coexpressed with the Na,K-ATPase alpha 1-subunit in Sf-9 cells using the baculovirus expression system. Specific and detergent-stable association is observed between the Na,K-ATPase alpha-subunit and the HNN and HNH chimeras, but not with the NHH, NHN, or HHN chimeras. Consistent with the Na,K-ATPase cytoplasmic domain as being necessary for alpha/alpha interactions, the full-length alpha-subunit stably associates with an alpha N-terminal deletion mutant (delta Gly2-Leu273), but not with an alpha cytoplasmic deletion mutant (delta Arg350-Pro785). In addition, the naturally occurring C-terminal truncated alpha 1 isoform, alpha 1T (delta Gly554 to C terminus), does not associated with the alpha 1-subunit in Sf-9 cells coexpressing both polypeptides. thus, a cytoplasmic region in the alpha-subunit (Gly554-Pro785) is necessary for specific alpha/alpha association. The same cytoplasmic region contains a strongly hydrophobic segment that, by analogy with oligomerization of water-soluble proteins, may form the interface of the extramembranous alpha/alpha contact site.

Amino Acid Sequence↗
PubMed1995

Loss of heterozygosity for chromosome 11 in primary human breast tumors is associated with poor survival after metastasis.

A common feature of the malignant progression of human tumors is loss of heterozygosity (LOH) for various regions of their genomes. Such events encompassing chromosomes 11p15 and 11q23 are frequent in human breast tumors. Here, we have analyzed genetic and clinical characteristics of a series of primary breast tumors in order to determine: (a) a more finely mapped estimate of the involved regions; (b) whether there is a relationship in the presentation of LOH between the two regions; and (c) whether a correlation exists between such LOH and any of the clinical parameters pertaining to each patient. We found that LOH for 11p15.5 and 11q23 occurred in 35 and 46% of the 86 primary breast carcinomas, respectively, but in none of the 10 benign tumors examined. The minimal region of LOH for 11p15 was in the approximately 2-megabase region between loci TH and D11S988. Twenty-nine % of the tumors showed LOH simultaneously at both 11p15 and 11q23, 5% had LOH only at 11p15.5, and 15% had LOH only at 11q23. Among these genetic groups, clinical features such as tumor size, involvement of auxiliary nodes, histological subtype, tumor grade, estrogen/progesterone receptor status, and patient age were not markedly different. However, LOH of 11q23 (either alone or in conjunction with LOH of 11p15) in the primary tumor was found to be highly predictive of aggressive postmetastatic disease course with substantially reduced survival (P = 0.0004; log rank test). We also observed a slight trend toward a more rapid development of metastatic lesions, without obvious site specificity, in patients with primary tumors showing LOH for chromosome 11 in the pathogenesis of human breast cancer; we suggest that its effects are late in the progression of this disease.

Breast Neoplasms↗
PubMed1995

Different oxidant sensitivities of the alpha 1 and alpha 2 isoforms of Na+/K(+)-ATPase expressed in baculovirus-infected insect cells.

Inhibition of Na+/K(+)-ATPase by partially reduced oxygen metabolites is an early event in the course of cell injury caused by oxidative stress. We showed before that isoforms of the enzyme obtained from different sources have different oxidant sensitivities. To evaluate the role of tissue-specific impurities in this difference, cDNAs of alpha 1 and alpha 2 isoforms were expressed in Sf-9 insect cells, and the effects of H2O2 on the resulting isolated enzymes were studied. The expressed alpha 2 was significantly more sensitive than alpha 1 to H2O2. These findings, together with our previous data showing different oxidant sensitivities of alpha 1 and alpha 3 in a cardiac enzyme preparation, indicate that differential oxidant sensitivities of Na+/K(+)-ATPase isoforms of various tissues are dictated by the primary sequences of alpha 1, alpha 2, and alpha 3 subunits.

Animals↗
PubMed1995

Kinetic properties of the alpha 2 beta 1 and alpha 2 beta 2 isozymes of the Na,K-ATPase.

The presence of multiple isoforms of the alpha and beta subunits of the Na,K-ATPase in most mammalian tissues has hindered the understanding of the roles of the individual isoforms in directing Na,K-ATPase function. Expression of the Na,K-ATPase subunits in insect cells using recombinant baculoviruses has proven to be a useful system for the study of Na,K-ATPase function. Using this system, we have expressed the rat Na,K-ATPase alpha 2 beta 1 and alpha 2 beta 2 isoforms in Sf-9 insect cells, a cell line derived from the ovary of the fall armyworm, Spodoptera frugiperda. Both beta 1 and beta 2 isoforms can efficiently assemble with the alpha 2 subunit to produce catalytically competent Na,K-ATPase molecules. The analysis of the kinetic properties of both isozymes showed that alpha 2 beta 1 and alpha 2 beta 2 have equivalent sensitivities to ouabain, and similar turnover numbers and apparent affinities for K+ and ATP. The dependence on Na+, however, differs between the isozymes, with alpha 2 beta 2 displaying a slightly higher apparent affinity for the cation than alpha 2 beta 1. In addition, the even greater kinetic differences between Na,K-ATPase isozymes varying in alpha isoforms may be important in further differentiating the enzyme. Thus, when compared to the rat alpha 1 beta 1 Na,K-ATPase expressed in Sf-9 cells, the alpha 2 beta 1 and alpha 2 beta 2 isozymes have a lower apparent affinity for K+ and a higher affinity for Na+ and ATP.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Genetic mapping of the mouse neuromuscular mutation kyphoscoliosis.

The ky mouse mutant, kyphoscoliosis, exhibits a degenerative muscle disease resulting in chronic deformation of the spinal column. Using an interspecific backcross segregating the ky mutation, we have mapped the ky locus to a small region of mouse chromosome 9. ky is nonrecombinant with the microsatellites D9Mit24 and D9Mit169 and lies in a conserved linkage group that encompasses human chromosome 3. s-Laminin (LAMS) and the gene for dystrophin-associated glycoprotein 1 (DAG1), which map to human chromosome 3, are both recombinant with ky, ruling them out as candidates.

Animals↗
PubMed1995

Comparison between the effects of tamoxifen and toremifene on the uterus in postmenopausal breast cancer patients.

Antiestrogens have been widely used in the treatment of breast cancer patients. We wanted to compare the uteral and vaginal effects of tamoxifen to those of toremifene. Thirty-one gynecologically asymptomatic postmenopausal breast cancer patients with an intact uterus were randomized to receive 20 mg of tamoxifen (N = 16) or 60 mg of toremifene (N = 15) as an adjuvant treatment. Gynecological examination with vaginal ultrasonography, Pap smear, endometrial biopsy, hysteroscopy, and curettage was performed before the treatment, and at 6 and 12 months of treatment. Endometrial thickness was found to increase significantly during the treatment to the same extent in both groups. Proliferation or other estrogenic effects in the endometrium were observed in 8 of 14 patients in the tamoxifen group and in 3 of 10 patients in the toremifene group. Three polyps occurred and previously present uterine fibroids increased in size in 3 of 10 patients during the study. Estrogenic changes in Pap smear were observed in all patients. There was no significant difference between tamoxifen and toremifene in any of the parameters investigated. Our results suggest that tamoxifen and toremifene produce comparable estrogenic effects in the uterus and vagina.

Adult↗
PubMed1995

Characterization of Na,K-ATPase isoform expression and activity in MDCK and Caco-2 epithelial cells.

The asymmetric distribution of the Na,K-ATPase in the plasma membrane of epithelial cells is essential to the establishment of the transepithelial Na+ gradient that supports the vectorial transport of ions and solutes. To investigate the changes that occur during the development of polarity, we have characterized Na,K-ATPase expression and activity in two epithelial cell culture lines, Madin Darby canine kidney (MDCK) and Caco-2 cells. RNA and immunoblot analysis of both cell lines demonstrate that only the alpha 1 and beta 1 isoforms are expressed in nonpolarized and polarized cultures. Interestingly, alpha 1 and beta 1 message increases in MDCK cells with the development of polarity, yet there is little change in the amount of protein for either subunit. In contrast, alpha 1 and beta 1 polypeptide expression increases in Caco-2 cells with the development of polarity, even though the amount of both transcripts decreases. The lack of correlation between the changes that occur at the level of the message and protein suggest that appropriate expression is mediated in part by a combination of transcriptional and translational events. Furthermore, while there was a slight decrease in activity in polarized MDCK cells, there was a 1.9 fold increase in Na,K-ATPase activity in the polarized Caco-2 cells as compared to nonpolarized cells. These results demonstrate that the regulation of Na,K-ATPase alpha 1 and beta 1 isoform expression is mediated by a combination of transcriptional and translational events during the development of polarity in both cell lines.

Animals↗
PubMed1994

The alpha-subunit of the Na,K-ATPase has catalytic activity independent of the beta-subunit.

All catalytic activities of the Na,K-ATPase have been ascribed to the alpha-subunit; however, normal activity requires the presence of the beta-subunit. Using recombinant baculoviruses to infect insect cells, we demonstrate that the alpha-subunit, without the beta-subunit, has catalytic activity. During the normal catalytic cycle of the Na,K-ATPase, the alpha-subunit is transiently phosphorylated by ATP at an aspartate residue. This phosphorylation requires Na+, in the presence of K+ the enzyme undergoes rapid dephosphorylation. In contrast, phosphorylation of the independent alpha-subunit by ATP occurs in the presence of Mg2+, does not require Na+ or K+, and is not affected by ouabain. The phosphorylation is, however, inhibited by EGTA and increasing ionic strength. Chemical properties of the alpha-subunit phosphointermediate are consistent with phosphorylation at the normal aspartyl residue. Membranes from cells infected with the recombinant alpha baculovirus exhibit an EGTA-sensitive Mg(2+)-ATPase activity that is not present in the uninfected cells. The Mg(2+)-ATPase of the alpha-infected cells is reduced under conditions of high ionic strength and completely inhibited by EGTA. Thus the phosphorylation of the unassociated alpha-subunit is representative of the ATPase activity of the enzyme. These results suggest that the alpha-subunit of the Na,K-ATPase can catalyze an activity not normally associated with the enzyme and demonstrate that the bea-subunit plays an important role in conferring normal activity to the enzyme complex.

Animals↗
PubMed1994

Loss of heterozygosity in sporadic human breast carcinoma: a common region between 11q22 and 11q23.3.

The development of sporadic human breast cancer is associated with the accumulation of genetic alterations on several chromosomes. In the case of chromosome 11, loss of heterozygosity (LOH) at loci on the short arm has been well documented and suggests the presence of a suppressor gene(s) at 11p15.5. However, the evidence for similar events on the long arm is less compelling. Here, we determined the prevalence of LOH for chromosome 11q in 44 malignant and 3 benign cases of unselected sporadic breast tumor samples. We found that alteration of chromosome 11q is common in the pathogenesis of breast cancer as 19 of 44 (43%) malignant tumor specimens exhibited LOH. Eleven (58%) of these genetic alterations were specific to the long arm of the chromosome. The smallest region of shared LOH places the target between 11q22 and 11q23.3, the same general region frequently altered in cancers of the ovary, colon, skin, and uterine cervix, perhaps indicating the location of a tumor suppressor gene or genes of importance in each of these different tumor types.

Breast Neoplasms↗
PubMed1994

The alpha subunit of the Na,K-ATPase specifically and stably associates into oligomers.

The Na,K-ATPase is a heterodimer consisting of an alpha and a beta subunit. Both Na,K-ATPase subunits are encoded by multigene families. Several isoforms for the alpha (alpha 1, alpha 2, and alpha 3) and beta (beta 1, beta 2, and beta 3) subunits have been identified. All these isoforms are capable of forming functionally active enzyme. Although there is general agreement that the Na,K-ATPase consists of alpha and beta subunits in equimolar amounts, the quaternary structure of the Na,K-ATPase and its functional significance is unknown. Several studies have demonstrated that the enzyme exists within the plasma membrane as an oligomer of alpha beta dimers. However, because the alpha beta protomer seems to be catalytically competent, the possibility exists that higher oligomers are irrelevant to function. The ability to express different alpha isoforms in insect cells and the availability of isoform-specific antibodies has provided the opportunity to test for the existence of stable and specific associations among alpha subunits. By coexpressing different alpha-subunit isoforms in cultured cells, we demonstrate that the Na,K-ATPase alpha subunits specifically and stably associate into oligomeric complexes. This same association among alpha-subunit isoforms was demonstrated in the native enzyme from rat brain. The interaction between Na,K-ATPase alpha subunits is highly specific. When the Na,K-ATPase alpha subunit is coexpressed with the alpha subunit from the H,K-ATPase, the H,K subunit does not associate with the Na,K subunit. Moreover, expression of the truncated alpha 1T isoform with the full-length alpha subunit demonstrates that the C-terminal portion of the polypeptide is important in the alpha-subunit association. Although these results do not clarify the functional role of alpha alpha associations, they do establish their highly specific nature and suggest that oligomerization of alpha beta protomers may be important to the stability and physiological regulation of the enzyme.

Animals↗
PubMed1994

Maturation of vaginal and endometrial epithelium in postmenopausal breast cancer patients receiving long-term tamoxifen.

To assess the estrogenic effects of tamoxifen on vaginal and endometrial epithelium and to investigate whether these changes are associated with any pathological findings in the endometrium, 53 postmenopausal breast cancer patients receiving long-term tamoxifen and 52 control breast cancer patients without any hormonal treatment were examined. Pathological findings in the endometrium were evaluated by hysteroscopy and curettage. The main outcome measures were the maturation index in Papanicolaou (Pap) smears, estrogen-like epithelial changes in the endometrium, serum concentrations of gonadotropins, sex hormone-binding globulin (SHBG), estradiol (E2), and testosterone (T). Informative Pap smears showed estrogenic effects in 89% (41/46) of the tamoxifen group and in 49% (22/45) of the control group, and in endometrial aspiration samples in 71% (32/45) and in 41% (19/46), respectively. These changes were associated with increased concentrations of serum E2 in the control group but not in the tamoxifen group. All five patients (11%) with endometrial polyps in the control group showed estrogenic endometrial changes, whereas among 14 women with polyps in the tamoxifen group, 9 showed estrogenic changes and 5 endometrial atrophy. Endometrial adenocarcinoma was found in 3 patients in the tamoxifen group and in 2 in the control group. Pap smears showed atrophy in 2 patients in the former and in one in the latter group. These findings confirmed estrogen-like effects of tamoxifen on the vaginal and endometrial epithelium in postmenopausal breast cancer patients, but these were not closely associated with benign or malignant endometrial lesions.

Adenocarcinoma↗
PubMed1994

Over-expression of human type I (placental) 3 beta-hydroxy-5-ene-steroid dehydrogenase/isomerase in insect cells infected with recombinant baculovirus.

Human type I placental 3 beta-hydroxy-5-ene-steroid dehydrogenase/steroid 5-->4-ene-isomerase (3 beta-HSD/isomerase) synthesizes androstenedione from fetal dehydroepiandrosterone and progesterone from pregnenolone. The full length cDNA that encodes type I 3 beta-HSD/isomerase was inserted into the baculovirus, Autographa californica multiple nucleocapsid polyhedrosis virus, and expressed in Spodoptera fungiperda (Sf-9) insect cells. Western blots showed that the baculovirus-infected Sf-9 cells produced an immunoreactive protein that co-migrated with purified placental 3 beta-HSD/isomerase. Ultracentrifugation localized the expressed enzyme activities in all the membrane-associated organelles of the Sf-9 cell (nuclear, mitochondrial and microsomal). Kinetic studies showed that the expressed enzyme has 3 beta-HSD and isomerase activities. The Michaelis-Menton constant is very similar for the 3 beta-HSD substrate, 5 alpha-androstan-3 beta- ol-17-one, in the Sf-9 cell homogenate (Km = 17.9 microM) and placental microsomes (Km = 16.7 microM). The 3 beta-HSD activity (Vmax = 14.5 nmol/min/mg) is 1.6-fold higher in the Sf-9 cell homogenate compared to placental microsomes (Vmax = 9.1 nmol/min/mg). The Km values are almost identical for the isomerase substrate, 5-androstene-3,17-dione, in the Sf-9 cell homogenate (Km = 14.7 microM) and placental microsomes (Km = 14.4 microM). The specific isomerase activity is 1.5-fold higher in the Sf-9 cells (Vmax = 25.7 nmol/min/mg) relative to placenta (Vmax = 17.2 nmol/min/mg). These studies show that our recombinant baculovirus system over-expresses fully active enzyme that is kinetically identical to native 3 beta-HSD/isomerase in human placenta.

Animals↗
PubMed1994

The alpha and beta subunits of the Na,K-ATPase can assemble at the plasma membrane into functional enzyme.

Synthesis and assembly of most oligomeric plasma membrane proteins occurs in the ER. However, the role the ER plays in oligomerization is unknown. We have previously demonstrated that unassociated alpha and beta subunits of the Na,K-ATPase are targeted to the plasma membrane when individually expressed in baculovirus-infected Sf-9 cells. This unique property allows us to determine if assembly of these two polypeptides is restricted to the ER, or if it can also occur at the plasma membrane. To investigate the assembly of the Na,K-ATPase we have taken advantage of the ability of baculovirus-infected cells to fuse. Lowering the extracellular pH of the infected cells triggers an endogenously expressed viral protein to initiate plasma membrane fusion. When individual Sf-9 cells expressing either the Na,K-ATPase alpha or beta subunits are plated together and subjected to a mild acidic shock, they form large syncytia. In the newly continuous plasma membrane the separate alpha and beta polypeptides associate and assemble into functional Na,K-ATPase molecules. However, a hybrid ATPase molecule consisting of a Na,K-ATPase alpha subunit and a H,K-ATPase beta subunit, which efficiently assembles in the ER of coinfected cells, does not assemble at the plasma membrane of fused cells. When cells expressing the Na,K-ATPase alpha subunit are fused to cells coexpressing the Na,K-ATPase beta subunit and the H,K-ATPase beta subunit, the Na,K-ATPase alpha subunit selectively assembles with the Na,K-ATPase beta subunit. However, when cells are coinfected and expressing all three polypeptides, the Na,K-ATPase alpha subunit assembles with both beta subunits in the ER, in what appears to be a random fashion. These experiments demonstrate that assembly between some polypeptides is restricted to the ER, and suggests that the ability of the Na,K-ATPase alpha and beta subunits to leave the ER and assemble at the plasma membrane may represent a novel mechanism of regulation of activity.

Animals↗
PubMed1994

Follicular dendritic cells have prognostic relevance in Hodgkin's disease.

The authors' previous study showed the presence of follicular dendritic cell (FDC) networks--though altered--in neoplastic areas, not only in the nodular lymphocyte predominance type, but also in other types of Hodgkin's disease. The present retrospective study was performed on 102 patients to determine whether the presence or absence of FDC networks, or parts of them, in neoplastic areas has prognostic relevance in Hodgkin's disease. Follicular dendritic cells were visualized with the monoclonal antibody Ki-FDC1P, which selectively stains FDCs in paraffin-embedded tissues. Univariate statistical analysis, in which nodular sclerosis (NS) and mixed cellularity (MC) types were combined, showed three prognostically different groups: the best prognosis was associated with nodular lymphocyte predominance cases; the worst with FDC-negative NS or MC cases; and an intermediate prognosis with FDC-positive NS or MC cases. In the NS group, the prognosis of FDC-positive cases was better than that of FDC-negative cases. After multivariate analysis, stepwise modeling identified three prognostic factors at diagnosis: stage (P = .001), FDC status (P = .001), and age (P = .06). The authors conclude that in the most common types of Hodgkin's disease (nodular lymphocyte predominance, NS, and MC), FDC status in the neoplastic area(s) bears prognostic relevance, a positive FDC status predicting a favorable prognosis and a negative FDC status an unfavorable one.

Adolescent↗
PubMed1994

Synthesis of ribosomal proteins during growth of Streptomyces coelicolor.

Changes in expression of ribosomal protein genes during growth and stationary phase of Streptomyces coelicolor A3(2) in liquid medium were studied. Proteins being synthesized were pulse-labelled with [35S]-methionine, separated by two-dimensional polyacrylamide gel electrophoresis, and quantified using the BioImage computer software. Most of the ribosomal proteins were synthesized throughout the life cycle. Exceptions were two proteins whose synthesis drastically decreased at the approach of stationary phase. These two proteins were identified in purified ribosomes as homologues of Escherichia coli ribosomal proteins L10 and L7/L12, using antibodies raised against fusion proteins between these ribosomal proteins and Escherichia coli beta-galactosidase. The genes (rplJ and rplL) encoding the L10 and L7/L12 proteins were contained in a 1.2 kb BamHI fragment that was cloned and sequenced. The linkage and order of the genes coincide with other L10-L7/L12 operons. However, L11 and L1 genes were not present immediately upstream of the L10 gene, as is the case for E. coli and other bacteria. Instead, two open reading frames of unknown function were found immediately upstream of the L10 gene, in an adjacent 1.9 kb BamHI fragment.

Base Sequence↗